How to save a float in NSUserDefaults

Question

I want to keep the value floatin NSUserDefaults.

I also need to check if the float value exists. If I don’t need to assign a value to it.

and get it ... for the above, I have the code below, but it gives me an error.

NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];

if ([defaults boolForKey:@"HANDWRITING_SIZE_SLIDER"] == YES) {
  self.sizeSlider.value = 10.0;
} else {
  self.sizeSlider.value = [[NSUserDefaults standardUserDefaults] floatForKey:@"HANDWRITING_SIZE_SLIDER"]];      
}

Thanks for any help

Answer 1

Use a class for this NSNumberand save it using the method setObject:forKey:so you can check if it exists.

I also suggest using constants as keys:

#define HANDWRITING_SIZE_SLIDER @"HSS"

Your code should be in the following lines:

NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];

if ([defaults objectForKey:HANDWRITING_SIZE_SLIDER] == nil) {
  //doesn't exist in NSUserDefaults, set to default value...
  self.sizeSlider.value = 10.0;
} else {
  self.sizeSlider.value = [[defaults objectForKey:HANDWRITING_SIZE_SLIDER] floatValue];
}

NSUserDefaults :

float sizeSliderValue = ...
[[NSUserDefaults standardUserDefaults] setObject:[NSNumber numberWithFloat:sizeSliderValue] forKey:HANDWRITING_SIZE_SLIDER];

Answer 2

:

-(IBAction)sliderAction:(id)sender
{
    float sliderValue = [sender floatValue];
    [[NSUserDefaults standardUserDefaults] setObject:[NSNumber numberWithFloat:sliderValue] forKey:@"keySliderValue"];

    NSLog(@"%@",[[NSUserDefaults standardUserDefaults] objectForKey:@"keySliderValue"]);
}